They definitely look like Platys to me. W*M didn't even tell you what they were?

Don't panic, there's no need to freak out. Unless you want more Platys and you isolate the fry and Moms in breeding traps, the Mom and other Platys withh eat the babies. If you do want to keep them, you'll need breeding traps that will isolate the fry from Mom. For feeding, I recommend Hikari First Bites or Liquid Fry Food (at Petsmart), or crushed tropical flakes.

http://www.fishforums.net/index.php?...swordtail+pics